Electrochemical evaluation of hot-dip galvanized steel (HDGS) coated with organic-inorganic hybrid sol-gel in cementitious materials

Abstract

Chromate based chemical conversion layers (CCC) are commonly used as surface treatments as they exhibit enhanced corrosion resistance and improved coating adhesion. However, the restrictions imposed on the use of hexavalent chromium, due to health and environmental concerns, has led to R&D efforts in the last few decades to search for new coating materials that fulfill the regulations and economic constraints imposed. Among these new coating materials, sol-gel methods are shown to be environmentally and economically advantageous in producing coatings that can provide effective corrosion protection. This work describes the studies performed for applying a sol-gel method to the production of organic-inorganic hybrid (OIH) coatings over HDGS reinforcement. The evaluation of their efficiency as a corrosion protection layer, to prevent the initial excessive reaction between mortar and the zinc, during the first days after concreting was studied.